The invention concerns a method and device for the treatment of liquids.
The liquids include wastewater, which encompasses, for example, solutions at various dilution strengths, seawater, brackish back water and the like, with particular emphasis on the runoff of once potable and industrial service waters. These input liquids are, in the following, designated as “feed-liquid.” The generic EP 1 363 855 B1 discloses a method wherein the wastewater is subjected to evaporation by contact with a flow of high temperature carrier gas followed by condensation. The possibility exists, giving consideration to predetermined pressure and temperature of the carrier gas, that the carrier gas may bear and entrain water vapor in quantities which cannot be overlooked. The carrier gas, as air or an inert gas, enters the treatment process from a trap or from a more elaborate condensate removal apparatus in which it has been freed of water vapor in accord with its given pressure and temperature. However, the quantity of water vapor still resident in this hot carrier gas can reduce to an appreciable degree a further absorption capability from a desired maximum. This interference can diminish the overall efficiency rating of the entire treatment method.
EP 1 363 855 B1 clearly establishes, that the condensate obtained from the condensate separator is to be conducted to a collection tank. The so collected condensate still contains remnants of the carrier gas and is sent through a heat exchanger, which serves as a drying unit. Simultaneously, another condensate separator also feeds into the same heat exchanger. This has the result that water vapor, entrained or present as humidity, is removed from the first condensate. The now dried gas is then returned to the carrier gas supply. In this way, and most importantly, a loss of carrier gas from the closed circulation system is avoided.
In consideration of the above, it is the purpose of the present invention to make available a method and a device especially for the treatment of liquids, for example, seawater, brackish backwash, and the like, whereby in a simple and effective manner, a gas stream of the greatest possible dryness is to be obtained.